1. Field of the Invention
The present invention relates to a dental cement composition. More specifically, the invention relates to a dental cement composition utilizing an acid-base reaction between a 4-methacryloxyethyl trimellitic acid aqueous solution and a powdered fluoroalumino silicate glass or a powdered metal oxide containing zinc oxide as a major component.
2. Description of the Related Art
In the dental field, when an inlay, a crown, a bridge, or the like, are to be adhered zinc phosphate cements, carboxylate cements, glass ionomer cements, or resin cements have been widely used.
Of these cements, since the dental zinc phosphate cements have no adhesive properties to a tooth structure, have a low pH value due to the presence of phosphoric acid and may cause stimulation to the tooth structure at the initiation time of setting, the frequency of their use is being decreased.
Though the dental carboxyl ate cements are a dental cement having low stimulation to the tooth structure, they have a defect that the mechanical strength is low and lack in reliability.
The dental glass ionomer cements have adhesive properties to the tooth structure and have a anti-caries function from their properties to release fluorine, thus accordingly, the dental glass ionomer cements were now widely used. In addition, since set products obtained from a dental glass ionomer cement have translucent and are superior in esthetics, they can also be applied to filling. However, as compared with the dental resin cements, the dental glass ionomer cements are low in bending strengths and have brittleness, and therefore, they have clinically a defect that when used for filling on an occlusion surface of a posterior tooth, edge portions are liable to break off.
On the other hand, the dental resin cements are superior in mechanical strengths but an exclusive dental adhesive is necessary for the adhesion to the tooth structure, due to the fact that such cement have no adhesive properties to the tooth structure. Accordingly, the dental resin cements have a defect that complicated adhesion steps are required to obtain a thorough adhesive strength.